U.S. patent application number 14/634389 was filed with the patent office on 2016-03-03 for temporarily bonding support substrate and semiconductor device manufacturing method.
This patent application is currently assigned to KABUSHIKI KAISHA TOSHIBA. The applicant listed for this patent is KABUSHIKI KAISHA TOSHIBA. Invention is credited to Kenro NAKAMURA.
Application Number | 20160064265 14/634389 |
Document ID | / |
Family ID | 55403335 |
Filed Date | 2016-03-03 |
United States Patent
Application |
20160064265 |
Kind Code |
A1 |
NAKAMURA; Kenro |
March 3, 2016 |
TEMPORARILY BONDING SUPPORT SUBSTRATE AND SEMICONDUCTOR DEVICE
MANUFACTURING METHOD
Abstract
According to one embodiment, there is provided a temporarily
bonding support substrate including an underlayer and a heat
generable layer. A device substrate is to be temporarily bonded to
the heat generable layer on an opposite side of the underlayer.
Inventors: |
NAKAMURA; Kenro; (Oita Oita,
JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
KABUSHIKI KAISHA TOSHIBA |
Tokyo |
|
JP |
|
|
Assignee: |
KABUSHIKI KAISHA TOSHIBA
Tokyo
JP
|
Family ID: |
55403335 |
Appl. No.: |
14/634389 |
Filed: |
February 27, 2015 |
Current U.S.
Class: |
156/247 ;
428/212; 428/312.6; 428/408; 428/446; 428/450 |
Current CPC
Class: |
H01L 2221/6834 20130101;
H01L 21/6835 20130101; H01L 25/0657 20130101; H01L 2221/68318
20130101; H01L 2224/94 20130101; H01L 2224/94 20130101; H01L
21/6836 20130101; H01L 2224/05009 20130101; H01L 2221/68327
20130101; H01L 2221/68381 20130101; H01L 2225/06541 20130101; H01L
2224/03002 20130101; H01L 2225/06565 20130101; H01L 2225/06513
20130101; H01L 21/76898 20130101; H01L 2224/03 20130101 |
International
Class: |
H01L 21/683 20060101
H01L021/683 |
Foreign Application Data
Date |
Code |
Application Number |
Aug 27, 2014 |
JP |
2014-173146 |
Claims
1. A temporarily bonding support substrate comprising: an
underlayer; and a heat generable layer provided on the underlayer,
a device substrate being to be temporarily bonded to the heat
generable layer on an opposite side of the underlayer.
2. The temporarily bonding support substrate according to claim 1,
wherein the heat generable layer has greater absorptivity to
electromagnetic waves than the underlayer.
3. The temporarily bonding support substrate according to claim 2,
wherein the heat generable layer has greater absorptivity to
infrared radiation than the underlayer.
4. The temporarily bonding support substrate according to claim 3,
wherein the underlayer is formed of a material made mainly of
silicon or silicon oxide, and the heat generable layer is formed of
a material made mainly of carbon or tungsten.
5. The temporarily bonding support substrate according to claim 2,
wherein the heat generable layer has greater absorptivity to
microwaves than the underlayer.
6. The temporarily bonding support substrate according to claim 5,
wherein the underlayer is formed of a material made mainly of
silicon oxide or silicon, and the heat generable layer includes a
high dielectric layer having metal particles diffused therein.
7. The temporarily bonding support substrate according to claim 2,
wherein the heat generable layer has greater absorptivity to high
frequency waves than the underlayer.
8. The temporarily bonding support substrate according to claim 7,
wherein the underlayer is formed of a material made mainly of
silicon oxide or silicon, and the heat generable layer is formed of
a material made mainly of metal.
9. The temporarily bonding support substrate according to claim 1,
wherein the heat generable layer has greater ability to
resistance-heat than the underlayer.
10. The temporarily bonding support substrate according to claim 1,
wherein the underlayer is formed of a material made mainly of
silicon oxide or silicon, and the heat generable layer is formed of
a material made mainly of nickel-chromium alloy or SiC ceramic.
11. The temporarily bonding support substrate according to claim 1,
further comprising a second heat generable layer placed between the
underlayer and the heat generable layer and, has greater
absorptivity to electromagnetic waves than the underlayer and
smaller absorptivity to electromagnetic waves than the heat
generable layer.
12. The temporarily bonding support substrate according to claim
11, wherein the second heat generable layer has composition that is
intermediate between composition of the underlayer and composition
of the heat generable layer.
13. The temporarily bonding support substrate according to claim 1,
further comprising a heat insulating layer which is placed between
the underlayer and the heat generable layer and which transmits
electromagnetic waves.
14. The temporarily bonding support substrate according to claim
13, wherein the heat insulating layer is formed of a material made
mainly of porous silicon or porous glass.
15. A semiconductor device manufacturing method comprising:
temporarily bonding a temporarily bonding support substrate having
a heat generable layer at a surface of the heat generable layer to
a device substrate via adhesive; making the heat generable layer
generate heat; and removing the temporarily bonding support
substrate from the device substrate.
16. The semiconductor device manufacturing method according to
claim 15, wherein the making the heat generable layer generate heat
includes causing heat deterioration of the adhesive.
17. The semiconductor device manufacturing method according to
claim 15, wherein the temporarily bonding support substrate further
has an underlayer, and the making the heat generable layer generate
heat includes irradiating electromagnetic waves onto the
temporarily bonding support substrate temporarily bonded to the
device substrate from the underlayer side so as to make the heat
generable layer generate heat.
18. The semiconductor device manufacturing method according to
claim 17, wherein the making the heat generable layer generate heat
includes irradiating infrared radiation onto the temporarily
bonding support substrate temporarily bonded to the device
substrate from the underlayer side so as to make the heat generable
layer generate heat.
19. The semiconductor device manufacturing method according to
claim 17, wherein the making the heat generable layer generate heat
includes irradiating microwaves onto the temporarily bonding
support substrate temporarily bonded to the device substrate from
the underlayer side so as to make the heat generable layer generate
heat.
20. The semiconductor device manufacturing method according to
claim 17, wherein the making the heat generable layer generate heat
includes irradiating high frequency waves onto the temporarily
bonding support substrate temporarily bonded to the device
substrate from the underlayer side so as to make the heat generable
layer generate heat.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] This application is based upon and claims the benefit of
priority from Japanese Patent Application No. 2014-173146, filed on
Aug. 27, 2014; the entire contents of which are incorporated herein
by reference.
FIELD
[0002] Embodiments described herein relate generally to a
temporarily bonding support substrate and a semiconductor device
manufacturing method.
BACKGROUND
[0003] It is sometimes required to temporarily bond a support
substrate to a device substrate so as to process the device
substrate and, after the process finishes, to remove the support
substrate from the device substrate. At this time, it is desired to
be able to smoothly remove the support substrate from the device
substrate.
BRIEF DESCRIPTION OF THE DRAWINGS
[0004] FIG. 1 is a cross-sectional view showing the configuration
of a temporarily bonding support substrate according to a first
embodiment;
[0005] FIG. 2 is a diagram showing a semiconductor device
manufacturing method using the temporarily bonding support
substrate according to the first embodiment;
[0006] FIG. 3 is a diagram showing the semiconductor device
manufacturing method using the temporarily bonding support
substrate according to the first embodiment;
[0007] FIG. 4 is a diagram showing the semiconductor device
manufacturing method using the temporarily bonding support
substrate according to the first embodiment;
[0008] FIG. 5 is a diagram showing the semiconductor device
manufacturing method using the temporarily bonding support
substrate according to the first embodiment;
[0009] FIG. 6 is a diagram showing the semiconductor device
manufacturing method using the temporarily bonding support
substrate according to the first embodiment;
[0010] FIG. 7 is a diagram showing the semiconductor device
manufacturing method using the temporarily bonding support
substrate according to the first embodiment;
[0011] FIG. 8 is a diagram showing the semiconductor device
manufacturing method using the temporarily bonding support
substrate according to the first embodiment;
[0012] FIG. 9 is a diagram showing the configuration of a
temporarily bonding support substrate according to a modified
example of the first embodiment;
[0013] FIG. 10 is a diagram showing the configuration of a
temporarily bonding support substrate according to another modified
example of the first embodiment;
[0014] FIG. 11 is a diagram showing the configuration of a
temporarily bonding support substrate according to yet another
modified example of the first embodiment;
[0015] FIG. 12 is a diagram showing the configuration of a
temporarily bonding support substrate and a semiconductor device
manufacturing method using the temporarily bonding support
substrate according to a second embodiment;
[0016] FIG. 13 is a diagram showing the configuration of a
temporarily bonding support substrate and a semiconductor device
manufacturing method using the temporarily bonding support
substrate according to a third embodiment; and
[0017] FIG. 14 is a diagram showing the configuration of a
temporarily bonding support substrate and a semiconductor device
manufacturing method using the temporarily bonding support
substrate according to a fourth embodiment.
DETAILED DESCRIPTION
[0018] In general, according to one embodiment, there is provided a
temporarily bonding support substrate including an underlayer and a
heat generable layer. The heat generable layer is provided on the
underlayer. A device substrate is to be temporarily bonded to the
heat generable layer on an opposite side of the underlayer.
[0019] Exemplary embodiments of a temporarily bonding support
substrate will be explained below in detail with reference to the
accompanying drawings. The present invention is not limited to the
following embodiments.
[0020] It should be noted that, in this specification, "a first
layer is provided on a second layer" includes not only a case where
a first layer is contacted on a second layer but also a case where
a third layer is sandwiched between the first layer and the second
layer.
First Embodiment
[0021] A temporarily bonding support substrate 10 according to the
first embodiment will be described using FIG. 1. FIG. 1 is a
cross-sectional view showing the configuration of the temporarily
bonding support substrate 10.
[0022] As a new approach to making semiconductor-device mounting
density higher, three-dimensional mounting technology is in the
spotlight in which semiconductor chips are stacked
three-dimensionally to produce a stacked-type semiconductor device.
In order to obtain a stacked-type semiconductor device, a plurality
of semiconductor chips need to be stacked in the
semiconductor-device packaging process. At this time, through
silicon vias (TSVs) extending through a device substrate
(semiconductor substrate) are formed, and the device substrate is
cut and divided with a dicing blade into individual semiconductor
chips. Then a stacked-type semiconductor device is formed by
stacking a plurality of semiconductor chips.
[0023] At this time, in order to easily form the through silicon
vias, the device substrate needs to be made thinner. Making a
device substrate thinner, in which elements are to be formed, is
performed by grinding and polishing the device substrate at the
back side, so that the thickness is finally, e.g., about 50 .mu.m.
Hence, the temporarily bonding support substrate 10 for stably
holding the device substrate in grinding and polishing needs to be
temporarily bonded to the front surface 30ia of the device
substrate 30i (see FIG. 2).
[0024] The temporarily bonding support substrate 10 is removed from
the device substrate (see FIG. 7) by the time that the device
substrate is divided into individual semiconductor chips. The types
of processes that are executed during the time from temporary
bonding to removal differ depending on the method of forming
junction electrodes between chips and the joining method. They may
be only back-side grinding and polishing or include a process of
forming openings in the device substrate (e.g., a silicon
substrate) (see FIG. 4) and a high-temperature film forming
process. That is, it is necessary to ensure stable adhering with
enduring the environment where mechanical separation and thermal
separation are likely to happen while temporarily bonded. In
contrast, it is desired to be able to smoothly remove the device
substrate from the support substrate when removing.
[0025] It is a highly difficult task to solve antinomic
propositions in temporarily bonding that are stable adhering while
temporarily bonded and easy removal when removing.
[0026] Facing these propositions, one could think of adopting
tactics in the material and structure of the adhering layer to deal
with them. To put it simply, one could think of a method which
provides a portion corresponding to a "removal layer" in the
adhering layer and dissolves this portion with a solvent or
decomposes it by laser light irradiation or the like so as to
separate the device substrate and the support substrate.
[0027] However, in a case where the portion is dissolved with a
solvent, because the adhering layer is of a three-layered structure
where a release layer is provided between an adhering layer on the
device substrate side and an adhering layer on the support
substrate side, there is the possibility that it may be difficult
to keep the thickness of the entire adhering layer uniform. As
variation in this thickness becomes greater, variation in the
thickness of the device substrate after made thinner also becomes
greater. Further, since the adhering layer is of a three-layered
structure, the production cost of the semiconductor device may
increase. Yet further, because directions in which the solvent
enters the release layer are limited to sideways of the release
layer, the processing time is likely to become longer.
[0028] In a case where the portion is decomposed by laser light
irradiation or the like, the material of the support substrate is
limited to a material whose transparency to light is high such as
glass, and it is difficult to use a material whose transparency to
light is low such as silicon, which is thought to be convenient in
practical use. Further, because the material of the adhering layer
is limited to a special material having the property of decomposing
by light irradiation, the production cost of the semiconductor
device is likely to increase.
[0029] In the present embodiment, stable adhering while temporarily
bonded and removal easiness when removing are realized not by
tactics in the material and structure of the adhering layer but by
tactics in the material and structure of the support substrate.
[0030] Specifically, the temporarily bonding support substrate 10
has an underlayer 11 and a heat generation layer 12 as shown in
FIG. 1. In the temporarily bonding support substrate 10, the
surface 12a of the heat generable layer 12 is to be temporarily
bonded to the device substrate 30i (see FIG. 2).
[0031] The underlayer 11 is required to have support rigidity to
support the device substrate 30i so as to be in a substantially
flat shape while the device substrate 30i is being ground and
polished with the temporarily bonding support substrate 10 being
temporarily bonded thereto. The underlayer 11 has a thickness and a
property in material according to the required support rigidity.
The underlayer 11 has a thickness of, e.g., 750 .mu.m or greater.
The underlayer 11 is formed of, e.g., a material made mainly of
silicon or silicon oxide. In a case where the underlayer 11 is
formed of a material made mainly of silicon, the production cost of
the temporarily bonding support substrate 10 can be easily reduced
as compared with a case where the underlayer 11 is formed of a
material made mainly of silicon oxide (glass).
[0032] The heat generable layer 12 is placed on the side of the
underlayer 11 which is to be temporarily bonded to the device
substrate 30i (see FIG. 2) via adhesive 20. For example, the heat
generable layer 12 is provided on the underlayer 11 and covers the
principal surface 11a on the side of the underlayer 11, the side
being to be temporarily bonded to the device substrate 30i. The
heat generable layer 12 can be formed by depositing material for it
on the principal surface 11a of the underlayer 11 by, e.g., a CVD
method or sputtering method. The heat generable layer 12 has a
thickness of, e.g., about 10 .mu.m.
[0033] The heat generable layer 12 is formed of a material that can
generate heat to cause heat deterioration the adhesive 20 with
being temporarily bonded to the device substrate 30i via the
adhesive 20. The heat generable layer 12 is greater in absorptivity
to electromagnetic waves of wavelengths longer than those of
visible light than the underlayer 11. The electromagnetic waves of
wavelengths longer than those of visible light are electromagnetic
waves of frequencies of 400 THz or less and are, for example,
infrared radiation. That is, the heat generable layer 12 is greater
in absorptivity to infrared radiation than the underlayer 11. The
heat generable layer 12 can be formed of a material made mainly of
carbon or tungsten. Or the heat generable layer 12 can be formed of
silicon highly increased in conductivity by doping an impurity.
Thus, when infrared radiation is irradiated toward the heat
generable layer 12 from the principal surface 11b side opposite to
the principal surface 11a of the underlayer 11, the heat generable
layer 12 can be made to generate, at the surface 12a, heat
necessary to cause heat deterioration of the adhesive 20 covering
the surface 12a of the heat generable layer 12 (see FIG. 2).
[0034] Next, a semiconductor device manufacturing method using the
temporarily bonding support substrate 10 will be described using
FIGS. 2 to 8.
[0035] In the present embodiment, the heat generable layer 12 to be
heated by electromagnetic waves of frequencies of 400 THz or less
is provided on the adhering surface side of the temporarily bonding
support substrate 10. The embodiment presents a technique in which,
after temporarily bonding, by irradiating electromagnetic waves to
heat the heat generable layer 12, a portion adjacent to the
interface of the adhesive 20 touching the heat generable layer 12
is subject to heat deterioration so that the temporarily bonding
support substrate 10 is removed from the device substrate 30. At
this time, because of adopting tactics in the structure and
material of the temporarily bonding support substrate 10 to perform
removal specific to the temporarily bonding support substrate 10,
the adhesive 20 can have general versatility.
[0036] Specifically, in the process shown in FIG. 2, the
temporarily bonding support substrate 10 having the underlayer 11
and the heat generable layer 12 is formed by depositing material
for the heat generable layer 12 on the principal surface 11a (see
FIG. 1) of the underlayer 11 by, e.g., a CVD method or sputtering
method. Meanwhile, the device substrate 30i is formed by forming a
device layer 33 on a surface of the semiconductor substrate 31i and
forming front-side electrodes 32 on the surface of the device layer
33. The device layer 33 may include a multilayer wiring structure
and elements such as transistors, and the front-side electrodes 32
may be electrically connected to the multilayer wiring structure
and elements in the device layer 33. The surface of the device
layer 33 and the surfaces of the front-side electrodes 32 form the
front surface 30ia of the device substrate 30i.
[0037] Next, the adhesive 20 is coated to cover the front surface
30ia of the device substrate 30i, and the temporarily bonding
support substrate 10 is temporarily bonded to the device substrate
30i via the adhesive 20. The adhesive 20 is, for example, of a
thermosetting type. The thermosetting temperature of the adhesive
20 is, for example, about 180.degree. C.
[0038] In the process shown in FIG. 3, the back surface 30ib of the
device substrate 30i is polished and ground by mechanical grinding
or the like. Thus, the device substrate 30j (the semiconductor
substrate 31j) becomes thinner. The device substrate 30j is made as
thin as, for example, about 50 .mu.m. Where the device substrate
30i is made thinner, after mechanical grinding is performed, the
back surface 30jb of the device substrate 30j can be made a mirror
surface by a CMP method or the like.
[0039] In the process shown in FIG. 4, regions 31jc (see FIG. 3)
corresponding to the front-side electrodes 32 in the device
substrate 30j (the semiconductor substrate 31j) are removed using a
photolithography technique and a dry etching technique. Thus, a
device substrate 30 having formed therein through holes 31d through
which the back surface of the device layer 33 is partially exposed,
can be obtained.
[0040] Then, an insulating film 34i is formed on the inner side
surfaces of the through holes 31d by a thermal CVD method or the
like. At this time, the adhesive 20 for temporarily bonding the
temporarily bonding support substrate 10 to the device substrate 30
is exposed to the thermal process (e.g., a substrate temperature
close to 200.degree. C.) while the support substrate 10 is
temporarily bonded, and hence a certain degree of heat resistance
is required of the adhesive 20. However, if the adhesive is too
high in heat resistance as is an inorganic adhesive such as water
glass, then it is difficult to remove after temporarily bonding.
From the viewpoint of moderate heat resistance, thermosetting
adhesive 20 can be used.
[0041] In the process shown in FIG. 5, by filling the through holes
31d with conductive material and patterning the back side, through
electrodes 35 having back-side electrodes 35a on the back side are
formed. The through electrodes 35 are insulated from the
semiconductor substrate 31 by the insulating film 34 covering the
inner side surfaces of the through holes 31d. The through
electrodes 35 may be electrically connected to the multilayer
wiring structure and elements in the device layer 33. Then, a
pickup tape 50 is stuck to the back-side electrodes 35a of the
through electrodes 35.
[0042] In the process shown in FIG. 6, the heat generable layer 12
is made to generate heat so as to cause heat deterioration of the
adhesive 20. That is, infrared radiation is irradiated onto the
temporarily bonding support substrate 10 temporarily bonded to the
device substrate 30 from the underlayer 11 side.
[0043] Specifically, an infrared radiation source 100 is placed in
a position facing the principal surface 11b of the underlayer 11 of
the temporarily bonding support substrate 10. As the infrared
radiation source 100, a lamp having high spectral emissivity in the
infrared range (e.g., an infrared lamp) may be used, or a halogen
lamp may be used. The infrared radiation source 100 is made to
operate so that infrared radiation emitted from the infrared
radiation source 100 is irradiated onto the temporarily bonding
support substrate 10 from the underlayer 11 side as indicated by
broken-line arrows in FIG. 6. The radiation intensity of the
infrared radiation source 100 can be set at, e.g., about 5
W/cm.sup.2. The irradiation time of infrared radiation by the
infrared radiation source 100 can be set at, e.g., about several
seconds.
[0044] At this time, of the temporarily bonding support substrate
10, absorptivity to infrared radiation in the heat generable layer
12 is greater than absorptivity to infrared radiation in the
underlayer 11. Thus, infrared radiation irradiated onto the
temporarily bonding support substrate 10 is efficiently absorbed by
the heat generable layer 12 to make the heat generable layer 12
generate heat. The heat generated in the heat generable layer 12
causes heat deterioration of a portion 21 of the adhesive 20
adjacent to the heat generable layer 12.
[0045] The portion 21 to be subject to heat deterioration is a
small portion of the adhesive existing adjacent to the interface
between the heat generable layer 12 of the temporarily bonding
support substrate 10 and the adhesive 20. Therefore, a small amount
of energy is enough to cause heat deterioration. By supplying this
thermal energy locally efficiently to the adhesive 20, the portion
21 that is a part of the adhesive 20 is subject to heat
deterioration. If the adhesive 20 is of a thermosetting type, the
portion 21 is heated to a temperature higher than the thermosetting
temperature (180.degree. C.). The portion 21 is heated to, e.g.,
about 200 to 350.degree. C. by the heat generable layer 12.
[0046] From the viewpoint of this locality and efficiency, not
hot-plate heating based on heat conduction but infrared-radiation
heating based on heat radiation is adopted. This
electromagnetic-wave heating (infrared-radiation heating) of the
heat generable layer 12 allows to suppress heating a portion 22
located on the side of device substrate 30 while locally heating
the portion 21 of the adhesive 20 adjacent to the interface with
the heat generable layer 12. Thus, a steep temperature profile can
be realized in which the portion 21 of the adhesive 20 adjacent to
the interface with the temporarily bonding support substrate 10
becomes high in temperature while the pickup tape 50 stuck to the
back of the device substrate 30 remains low in temperature.
[0047] From the viewpoint of maintaining the steep temperature
profile for a long time, the heat generable layer 12 needs to be of
an appropriate thickness (for example, about 10 .mu.m thick). This
is because, if the heat generable layer 12 is too thick, an excess
of heat from the heat generable layer 12 is conducted from the
adhesive 20 to the device substrate 30 to the pickup tape 50, so
that the pickup tape 50 may increase in temperature to suffer
thermal damage.
[0048] In the process shown in FIG. 7, the temporarily bonding
support substrate 10 is removed from the device substrate 30. The
specific method of removing is decided on depending on to what
extent the adhesiveness to the temporarily bonding support
substrate 10 of the adhesive 20 is restored when portion 21 having
been subject to heat deterioration has re-solidified.
[0049] At this time, if the adhesive 20 is of a thermosetting type,
heat deterioration when heated is the thermal decomposition of
cross-linked structures in the portion 21, and thus the
adhesiveness is hardly likely to recover even when the temperature
drops. That is, the removal need not be performed while the heat
generable layer 12 is heated to cause heat deterioration of the
portion 21. Because the removal can be performed when the
temperature has dropped, an usual room-temperature removal method
can be used after the infrared radiation source 100 is
evacuated.
[0050] Alternatively, if the adhesive 20 is of a hot-melting type,
heat deterioration when heated is the melting and softening of the
portion 21, and thus the adhesiveness may recover when the
temperature drops. If the adhesiveness recovers when the
temperature drops, then the removal needs to be performed while the
heat generable layer 12 is being heated to cause heat deterioration
of the portion 21. Therefore, there are hurdles associated with the
use that the removal needs to be performed in such a way as not to
interfere with the infrared radiation source 100, and so on. For
example, a method is adopted which slides the temporarily bonding
support substrate 10 sideways to remove with the placement of the
infrared radiation source 100 remaining the same. Or a method which
moves not the temporarily bonding support substrate 10 but the
device substrate 30 having the pickup tape 50 stuck thereto to
remove can also be adopted. This fact is true of thermoplastic
adhesive 20. Both the hot-melting type and the thermoplastic type
of adhesive 20 can be used in this embodiment, but the
thermosetting adhesive 20 is convenient to use.
[0051] That is, because the portion 21 having been subject to heat
deterioration is weakened in chemical cohesion, it can be easily
separated from the other portion 22. Thus, the temporarily bonding
support substrate 10 to which the portion 21' is adhering can be
removed from the device substrate 30 to which the portion 22' is
adhering.
[0052] In the process shown in FIG. 8, the portion 22' adhering to
the device substrate 30 is removed from the device substrate 30.
That is, after the removal in the process shown in FIG. 7, the
portion 22' of the adhesive remains adhering to the device
substrate 30, but the entire surface of the portion 22' is exposed.
Thus, the portion 22' can be easily removed by usual processing
such as wet etching or dry etching. For example, it is removed by
wet etching with an organic solvent.
[0053] It should be noted that, although part of the portion 21' of
the adhesive 20 may remain adhering to the temporarily bonding
support substrate 10, it can be washed off with an organic solvent
to reuse the temporarily bonding support substrate 10.
[0054] The obtained device substrate 30 is cut and divided with a
dicing blade, and removed from the pickup tape 50, into a plurality
of semiconductor chips. Then the plurality of divided-into
semiconductor chips are stacked, and the back-side electrodes 35a
of a semiconductor chip located above and the front-side electrodes
32 of a semiconductor chip located below are joined. By this means,
the plurality of semiconductor chips are electrically connected via
the through electrodes 35 to form a stacked-type semiconductor
device.
[0055] As described above, in the first embodiment, in the
temporarily bonding support substrate 10, the heat generable layer
12 is placed on the side of the underlayer 11 which is temporarily
bonded to the device substrate 30 via the adhesive 20. The heat
generable layer 12 in the state of being temporarily bonded to the
device substrate 30 via the adhesive 20 can generate heat to cause
heat deterioration of the adhesive 20. By this means, chemical
cohesion in the portion having been subject to heat deterioration
in the adhesive 20 can be weakened, and with the portion weakened
in chemical cohesion, the temporarily bonding support substrate 10
can be separated from the device substrate 30. As a result, in a
case where the temporarily bonding support substrate 10 is
temporarily bonded to the device substrate 30 via the adhesive 20
strengthened in adhesiveness, the temporarily bonding support
substrate 10 can be smoothly removed from the device substrate 30
after the process finishes. That is, strong adhering while
temporarily bonded and easy removal after temporarily bonding can
both be realized.
[0056] Further, in the first embodiment, strong adhering while
temporarily bonded and easy removal after temporarily bonding can
be realized by adopting tactics in the temporarily bonding support
substrate 10, and hence it is easy to make the adhesive 20 have
general versatility.
[0057] Yet further, in the first embodiment, in the temporarily
bonding support substrate 10, the heat generable layer 12 is
greater in absorptivity to electromagnetic waves of wavelengths
longer than those of visible light (e.g., infrared radiation) than
the underlayer 11. Thus, when electromagnetic waves of wavelengths
longer than those of visible light are irradiated toward the heat
generable layer 12 from the principal surface 11b side of the
underlayer 11, the heat generable layer 12 can be made to
efficiently absorb the irradiated electromagnetic waves (e.g.,
infrared radiation) so as to generate heat.
[0058] In the first embodiment, in the temporarily bonding support
substrate 10, the underlayer 11 is formed of a material made mainly
of silicon or silicon oxide, and the heat generable layer 12 is
formed of a material made mainly of carbon or tungsten. Thus,
absorptivity to infrared radiation in the heat generable layer 12
can be made greater than absorptivity to infrared radiation in the
underlayer 11. Further, if the underlayer 11 is formed of a
material made mainly of silicon, the production cost of the
temporarily bonding support substrate 10 can be easily reduced.
[0059] In the first embodiment, in the semiconductor device
manufacturing method, the surface 12a of the heat generable layer
12 in the temporarily bonding support substrate 10 is temporarily
bonded to the device substrate 30 via the adhesive 20. Then, by
making the heat generable layer 12 generate heat to cause heat
deterioration of the adhesive 20, the temporarily bonding support
substrate 10 is removed from the device substrate 30. By this
means, chemical cohesion in the portion having been subject to heat
deterioration in the adhesive 20 can be weakened, and with the
portion weakened in chemical cohesion, the temporarily bonding
support substrate 10 can be easily removed from the device
substrate 30. As a result, in a case where the temporarily bonding
support substrate 10 is temporarily bonded to the device substrate
30 via the adhesive 20 strengthened in adhesiveness, the
temporarily bonding support substrate 10 can be smoothly removed
from the device substrate 30 after the process finishes. That is,
strong adhering while temporarily bonded and easy removal after
temporarily bonding can both be realized.
[0060] Further, in the first embodiment, in the semiconductor
device manufacturing method, by irradiating electromagnetic waves
of wavelengths longer than those of visible light onto the
temporarily bonding support substrate 10 temporarily bonded to the
device substrate 30 from the underlayer 11 side (infrared heating),
the heat generable layer 12 is made to generate heat. By this
means, the portion 21 of the adhesive 20 adjacent to the interface
with the temporarily bonding support substrate 10 can be locally
heated so as to cause heat deterioration of the portion 21 of the
adhesive 20 with suppressing the influence of heat on the device
substrate 30 side.
[0061] Yet further, in the first embodiment, in the semiconductor
device manufacturing method, the temporarily bonding support
substrate 10 can be temporarily bonded to the device substrate 30
via the thermosetting adhesive 20. Then, by making the heat
generable layer 12 generate heat to cause heat deterioration of the
adhesive 20, cross-linked structures in the portion 21 of the
adhesive 20 can be thermally decomposed. By this means,
adhesiveness in the portion 21 of the adhesive 20 can be made not
to recover even when the temperature drops, and hence the
temporarily bonding support substrate 10 can be easily removed from
the device substrate 30.
[0062] It should be noted that a temporarily bonding support
substrate 110 may have a plurality of heat generable layers 121,
122 as shown in FIG. 9. The heat generable layer 122 is placed on
the underlayer 11. The heat generable layer 122 covers the
principal surface 11a of the underlayer 11. The heat generable
layer 121 is placed on the heat generable layer 122. The heat
generable layer 121 covers the surface 122a of the heat generable
layer 122. The heat generable layer 121 is greater in absorptivity
to infrared radiation than the heat generable layer 122. The heat
generable layer 122 is greater in absorptivity to infrared
radiation than the underlayer 11. The heat generable layer 122 has
composition that is intermediate between the composition of the
underlayer 11 and the composition of the heat generable layer 121.
The temporarily bonding support substrate 110 can be formed such
that in terms of the composition ratio of carbon, the heat
generable layer 121>the heat generable layer 122>the
underlayer 11 as shown in FIG. 9, for example. Thus, when infrared
radiation is irradiated toward the heat generable layers 121, 122
from the principal surface 11b side opposite to the principal
surface 11a of the underlayer 11, heat generated in the heat
generable layers 121, 122 can be collected from the heat generable
layer 122 to the heat generable layer 121. As a result, heat
necessary to cause heat deterioration of the adhesive 20 (see FIG.
2) covering the surface 121a of the heat generable layer 121 can be
efficiently generated at the surface 121a of the heat generable
layer 121.
[0063] Or a temporarily bonding support substrate 110' may have a
heat generable layer 123 having gradient composition as shown in
FIG. 10. The heat generable layer 123 is placed on the underlayer
11. The heat generable layer 123 covers the principal surface 11a
of the underlayer 11. The heat generable layer 123 is greater in
absorptivity to infrared radiation than the underlayer 11. The heat
generable layer 123 is formed such that absorptivity to infrared
radiation gradually increases when going from the underlayer 11
side to a surface 123a side. The temporarily bonding support
substrate 110' can be formed such that the composition ratio of
carbon of the heat generable layer 123 gradually increases when
going from the underlayer 11 side to the surface 123a side as shown
in FIG. 10, for example. Thus, when infrared radiation is
irradiated toward the heat generable layer 123 from the principal
surface 11b side opposite to the principal surface 11a of the
underlayer 11, heat generated in the heat generable layer 123 can
be moved from the inside of the heat generable layer 123 to the
surface 123a. As a result, heat necessary to cause heat
deterioration of the adhesive 20 (see FIG. 2) covering the surface
123a of the heat generable layer 123 can be efficiently generated
at the surface 123a of the heat generable layer 123.
[0064] Or a temporarily bonding support substrate 110'' may be
formed such that heat generated in the heat generable layer 12 is
held in the heat generable layer 12 as shown in FIG. 11. For
example, the temporarily bonding support substrate 110'' further
has a heat insulating layer 113. The heat insulating layer 113 is
placed between the underlayer 11 and the heat generable layer 12.
The heat insulating layer 113 is sandwiched between the underlayer
11 and the heat generable layer 12. The heat insulating layer 113
is formed of a material that easily transmits electromagnetic waves
of wavelengths longer than those of visible light (e.g., infrared
radiation) and easily blocks heat generated in the heat generable
layer 12. The heat insulating layer 113 should be resistant to
heat. The heat insulating layer 113 is formed of a porous material
and may be formed of a material made mainly of, e.g., porous
silicon or porous glass. In this case, even if the adhesive 20 is
of the hot-melting type or thermoplastic type in the process of
FIG. 6, heat generated in the heat generable layer 12 can be held
in the heat generable layer 12. Thus, even when some time has
elapsed after infrared radiation has been irradiated, the removal
can be performed, and thereby an usual room-temperature removal
method can be used after the infrared radiation source 100 is
evacuated.
Second Embodiment
[0065] Next, a temporarily bonding support substrate 210 according
to the second embodiment will be described. Description will be
made below focusing on the differences from the first
embodiment.
[0066] Although the first embodiment illustratively describes the
case where the temporarily bonding support substrate 10 has a
structure suitable for infrared heating, the second embodiment will
illustratively describe the case where the temporarily bonding
support substrate 210 has a structure suitable for dielectric
heating.
[0067] Specifically, as shown in FIG. 12, the temporarily bonding
support substrate 210 has a heat generable layer 212 instead of the
heat generable layer 12 (see FIG. 1). FIG. 12 is a diagram showing
the configuration of the temporarily bonding support substrate 210.
The heat generable layer 212 is greater in absorptivity to
microwaves than the underlayer 11. The heat generable layer 212 is
required to have a large loss factor of dielectric loss (=.di-elect
cons..times.tan .delta., where .di-elect cons. is a permittivity
and tan .delta. is a dielectric tangent). For example, the heat
generable layer 212 includes a high dielectric layer having metal
particles diffused therein. The structure where particles are
diffused is advantageous in enlarging tan .delta., so that a
material of that structure has an .di-elect cons. large in
value.
[0068] In the semiconductor device manufacturing method, instead of
the process shown in FIG. 6, the process shown in FIG. 12 is
executed. FIG. 12 is a cross-sectional view showing a process of
the semiconductor device manufacturing method using the temporarily
bonding support substrate 210.
[0069] In the process shown in FIG. 12, microwaves are irradiated
onto the temporarily bonding support substrate 210 temporarily
bonded to the device substrate 30 from the underlayer 11 side.
[0070] Specifically, an electrode (microwave source) 200 is placed
in a position facing the principal surface 11b of the underlayer 11
of the temporarily bonding support substrate 210, and an electrode
201 is placed on the opposite side of the temporarily bonding
support substrate 210 and the device substrate 30 from the
electrode 200. High-frequency power is supplied across the
electrodes 200 and 201 from a high-frequency power supply 202.
Thus, microwaves emitted from the electrode 200 are irradiated onto
the temporarily bonding support substrate 210 from the underlayer
11 side as indicated by broken-line arrows in FIG. 12.
[0071] At this time, of the temporarily bonding support substrate
210, absorptivity to microwaves in the heat generable layer 212 is
greater than absorptivity to microwaves in the underlayer 11. Thus,
microwaves irradiated onto the temporarily bonding support
substrate 210 are efficiently absorbed by the heat generable layer
212 to make the heat generable layer 212 generate heat. The heat
generated in the heat generable layer 212 causes heat deterioration
of the portion 21 of the adhesive 20 adjacent to the heat generable
layer 212.
[0072] Note that, because the temporarily bonding support substrate
210 and the device substrate 30 are placed between the electrodes
200 and 201, it may be difficult to perform removal operation while
they stay in this position in the process shown in FIG. 7. In a
case where the adhesive 20 is of a thermosetting type, heat
deterioration when heated is the thermal decomposition of
cross-linked structures in the portion 21, and thus the
adhesiveness is hardly likely to recover even when the temperature
drops. That is, the removal need not be performed while the heat
generable layer 212 is heated to cause heat deterioration of it.
Because the removal can be performed when the temperature has
dropped, an usual room-temperature removal method can be used after
the electrodes 200 and 201 are evacuated.
[0073] As described above, in the second embodiment, in the
temporarily bonding support substrate 210, the heat generable layer
212 is greater in absorptivity to microwaves than the underlayer
11. Thus, when microwaves are irradiated toward the heat generable
layer 212 from the principal surface 11b side of the underlayer 11,
the heat generable layer 212 can be made to efficiently absorb the
irradiated microwaves to make the heat generable layer 212 generate
heat.
[0074] Further, in the second embodiment, in the temporarily
bonding support substrate 210, the underlayer 11 is formed of a
material made mainly of silicon or silicon oxide, and the heat
generable layer 212 includes a high dielectric layer having metal
particles diffused therein. Thus, absorptivity to microwaves in the
heat generable layer 212 can be made greater than absorptivity to
microwaves in the underlayer 11. Further, if the underlayer 11 is
formed of a material made mainly of silicon, the production cost of
the temporarily bonding support substrate 210 can be easily
reduced.
[0075] Further, in the second embodiment, in the semiconductor
device manufacturing method, by irradiating microwaves onto the
temporarily bonding support substrate 210 temporarily bonded to the
device substrate 30 from the underlayer 11 side (dielectric
heating), the heat generable layer 212 is made to generate heat. By
this means, the portion 21 of the adhesive 20 adjacent to the
interface with the temporarily bonding support substrate 210 can be
locally heated so as to cause heat deterioration of the portion 21
of the adhesive 20 with suppressing the influence of heat on the
device substrate 30 side.
Third Embodiment
[0076] Next, a temporarily bonding support substrate 310 according
to the third embodiment will be described. Description will be made
below focusing on the differences from the first embodiment.
[0077] Although the first embodiment illustratively describes the
case where the temporarily bonding support substrate 10 has a
structure suitable for infrared heating, the third embodiment will
illustratively describe the case where the temporarily bonding
support substrate 310 has a structure suitable for induction
heating.
[0078] Specifically, as shown in FIG. 13, the temporarily bonding
support substrate 310 has a heat generable layer 312 instead of the
heat generable layer 12 (see FIG. 1). FIG. 13 is a diagram showing
the configuration of the temporarily bonding support substrate 310.
The heat generable layer 312 is greater in absorptivity to high
frequency waves than the underlayer 11. The heat generable layer
312 is required to be made of a material in which eddy current is
likely to occur according to magnetic flux that it receives, and it
is effective for the material to have large loss power due to
magnetic hysteresis. For example, the heat generable layer 312 may
be formed of a material made mainly of metal, especially a material
made mainly of a substance large in permeability such as iron,
cobalt, or nickel. In the material made mainly of metal, eddy
current is likely to occur according to magnetic flux that it
receives. The material large in permeability is large in loss power
due to magnetic hysteresis.
[0079] Further, in the semiconductor device manufacturing method,
instead of the process shown in FIG. 6, the process shown in FIG.
13 is executed. FIG. 13 is a cross-sectional view showing a process
of the semiconductor device manufacturing method using the
temporarily bonding support substrate 310.
[0080] In the process shown in FIG. 13, high frequency waves are
irradiated onto the temporarily bonding support substrate 310
temporarily bonded to the device substrate 30 from the underlayer
11 side.
[0081] Specifically, a coil (high frequency source) 300 is placed
to accommodate the temporarily bonding support substrate 310 and
the device substrate 30 inside it. Then high-frequency power is
supplied to the coil 300 from a high-frequency power supply (not
shown). Thus, high frequency waves emitted from the coil 300 are
irradiated onto the temporarily bonding support substrate 310 from
the underlayer 11 side as indicated by broken-line arrows in FIG.
13.
[0082] At this time, of the temporarily bonding support substrate
310, absorptivity to high frequency waves in the heat generable
layer 312 is greater than absorptivity to high frequency waves in
the underlayer 11. Thus, high frequency waves irradiated onto the
temporarily bonding support substrate 310 are efficiently absorbed
by the heat generable layer 312 to make the heat generable layer
312 generate heat. The heat generated in the heat generable layer
312 causes heat deterioration of the portion 21 of the adhesive 20
adjacent to the heat generable layer 312.
[0083] Note that, because the temporarily bonding support substrate
310 and the device substrate 30 are placed inside the coil 300, it
may be difficult to perform removal operation while they stay in
this position in the process shown in FIG. 7. Where the adhesive 20
is of a thermosetting type, heat deterioration when heated is the
thermal decomposition of cross-linked structures in the portion 21,
and thus the adhesiveness is hardly likely to recover even when the
temperature drops. That is, the removal need not be performed while
the heat generable layer 312 is heated to cause heat deterioration
of it. Because the removal can be performed when the temperature
has dropped, a usual room-temperature removal method can be used
after the coil 300 is evacuated.
[0084] As described above, in the third embodiment, in the
temporarily bonding support substrate 310, the heat generable layer
312 is greater in absorptivity to high frequency waves than the
underlayer 11. Thus, when high frequency waves are irradiated
toward the heat generable layer 312 from the principal surface 11b
side of the underlayer 11, the heat generable layer 312 can be made
to efficiently absorb the irradiated high frequency waves to make
the heat generable layer 312 generate heat.
[0085] Further, in the third embodiment, in the temporarily bonding
support substrate 310, the underlayer 11 is formed of a material
made mainly of silicon or silicon oxide, and the heat generable
layer 312 is formed of a material made mainly of metal. Thus,
absorptivity to high frequency waves in the heat generable layer
312 can be made greater than absorptivity to high frequency waves
in the underlayer 11. Further, if the underlayer 11 is formed of a
material made mainly of silicon, the production cost of the
temporarily bonding support substrate 310 can be easily
reduced.
[0086] Further, in the third embodiment, in the semiconductor
device manufacturing method, by irradiating high frequency waves
onto the temporarily bonding support substrate 310 temporarily
bonded to the device substrate 30 from the underlayer 11 side
(induction heating), the heat generable layer 312 is made to
generate heat. By this means, the portion 21 of the adhesive 20
adjacent to the interface with the temporarily bonding support
substrate 310 can be locally heated so as to cause heat
deterioration of the portion 21 of the adhesive 20 with suppressing
the influence of heat on the device substrate 30 side.
Fourth Embodiment
[0087] Next, a temporarily bonding support substrate 410 according
to the fourth embodiment will be described. Description will be
made below focusing on the differences from the first
embodiment.
[0088] Although the first embodiment illustratively describes the
case where the temporarily bonding support substrate 10 has a
structure suitable for infrared heating, the fourth embodiment will
illustratively describe the case where the temporarily bonding
support substrate 410 has a structure suitable for resistance
heating.
[0089] Specifically, as shown in FIG. 14, the temporarily bonding
support substrate 410 has a heat generable layer 412 instead of the
heat generable layer 12 (see FIG. 1) and further has electrodes
414a, 414b and an insulating layer 415. FIG. 14 is a diagram
showing the configuration of the temporarily bonding support
substrate 410. The electrodes 414a, 414b are electrically connected
to opposite ends of the heat generable layer 412. The electrodes
414a, 414b can be formed, for example, by coating silver paste on
opposite ends of the heat generable layer 412. The insulating layer
415 electrically insulates the heat generable layer 412 from the
underlayer 11. The insulating layer 415 can be formed by depositing
an insulator (e.g., silicon oxide) on the principal surface 11a of
the underlayer 11 by a CVD method or the like. Note that, if the
underlayer 11 is formed of an insulator such as silicon oxide
(glass), the insulating layer 415 may be omitted.
[0090] The heat generable layer 412 is greater in the ability to
resistance-heat (easiness to enlarge
current.times.(resistance).sup.2) than the underlayer 11. For
example, the heat generable layer 412 may be formed of a material
made mainly of nickel-chromium alloy or a material made mainly of
SiC ceramic. The heat generable layer 412 may be formed by
depositing a material made mainly of nickel-chromium alloy on the
surface 415a of the insulating layer 415 by a CVD method or the
like or by depositing a material made mainly of SiC ceramic on the
surface 415a of the insulating layer 415 by chemical vapor
deposition or the like. In a case where the heat generable layer
412 is formed of a material made mainly of SiC ceramic, the
resistance value decreases with an increase in the temperature at
close to use temperatures, so that the thermal runaway of the heat
generable layer 412 can be easily suppressed.
[0091] In the semiconductor device manufacturing method, instead of
the process shown in FIG. 6, the process shown in FIG. 14 is
executed. FIG. 14 is a cross-sectional view showing a process of
the semiconductor device manufacturing method using the temporarily
bonding support substrate 410.
[0092] In the process shown in FIG. 14, the temporarily bonding
support substrate 410 temporarily bonded to the device substrate 30
is resistance-heated.
[0093] Specifically, a direct-current power supply 402 is connected
to the electrodes 414a, 414b of the temporarily bonding support
substrate 410 via lines 401, 400. Thus, direct-current power is
supplied from the direct-current power supply 402 to the heat
generable layer 412.
[0094] At this time, in the temporarily bonding support substrate
410, the ability to resistance-heat of the heat generable layer 412
is greater than the ability to resistance-heat of the underlayer
11. Thus, direct-current power supplied to the temporarily bonding
support substrate 410 is efficiently supplied to the heat generable
layer 412 to make the heat generable layer 412 generate heat. The
heat generated in the heat generable layer 412 causes heat
deterioration of the portion 21 of the adhesive 20 adjacent to the
heat generable layer 412.
[0095] As described above, in the fourth embodiment, of the
temporarily bonding support substrate 410, the heat generable layer
412 is greater in the ability to resistance-heat than the
underlayer 11. Thus, when direct-current power is supplied to the
temporarily bonding support substrate 410, the direct-current power
can be efficiently supplied to the heat generable layer 412 to make
the heat generable layer 412 generate heat.
[0096] Further, in the fourth embodiment, in the temporarily
bonding support substrate 410, the underlayer 11 is formed of a
material made mainly of silicon or silicon oxide, and the heat
generable layer 412 is formed of a material made mainly of
nickel-chromium alloy or SiC ceramic. Thus, the ability to
resistance-heat of the heat generable layer 412 can be made greater
than the ability to resistance-heat of the underlayer 11. Further,
where the heat generable layer 412 is formed of a material made
mainly of SiC ceramic, the resistance value decreases with an
increase in the temperature at close to use temperatures, so that
the thermal runaway of the heat generable layer 412 can be easily
suppressed.
[0097] Further, in the fourth embodiment, in the semiconductor
device manufacturing method, by supplying direct-current power to
the temporarily bonding support substrate 410 temporarily bonded to
the device substrate 30 via the electrodes 414a, 414b on opposite
ends of the heat generable layer 412 (resistance heating), the heat
generable layer 412 is made to generate heat. By this means, the
portion 21 of the adhesive 20 adjacent to the interface with the
temporarily bonding support substrate 410 can be locally heated so
as to cause heat deterioration of the portion 21 of the adhesive 20
with suppressing the influence of heat on the device substrate 30
side.
[0098] It should be noted that, although the first to fourth
embodiments exemplify the heat generable layer that is greater in
absorptivity to electromagnetic waves of wavelengths longer than
those of visible light than the underlayer 11, the heat generable
layer may be greater in absorptivity to electromagnetic waves of
wavelengths of visible light than the underlayer 11. If the
underlayer 11 is formed of material whose transparency to visible
light is high such as glass, it is possible for visible light to be
irradiated toward the heat generable layer to generate heat
necessary to cause heat deterioration of the adhesive 20 covering
the surface of the heat generable layer.
[0099] Alternatively, the heat generable layer may be greater in
absorptivity to electromagnetic waves of wavelengths shorter than
those of visible light than the underlayer 11. If the underlayer 11
is formed of material whose transparency to electromagnetic waves
of wavelengths shorter than those of visible light is high such as
glass, it is possible for visible light to be irradiated toward the
heat generable layer to generate heat necessary to cause heat
deterioration of the adhesive 20 covering the surface of the heat
generable layer.
[0100] While certain embodiments have been described, these
embodiments have been presented by way of example only, and are not
intended to limit the scope of the inventions. Indeed, the novel
embodiments described herein may be embodied in a variety of other
forms; furthermore, various omissions, substitutions and changes in
the form of the embodiments described herein may be made without
departing from the spirit of the inventions. The accompanying
claims and their equivalents are intended to cover such forms or
modifications as would fall within the scope and spirit of the
inventions.
* * * * *